<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

</head>
<body>
<form th:action="@{/test}">
    <select name="tag"  multiple>
        <option  value="volvo">Volvo</option>
        <option value="saab">Saab</option>
        <option value="opel">Opel</option>
        <option value="audi">Audi</option>
    </select>
    <input type="submit" value="提交">
</form>
</body>
</html>